I've got an old (but still functional) Xantrex 2000R and a Blue Sky 2000. The goal is to be able to track amps getting put back into the batteries, so the wiring from the solar panels intuitively should go panels -> MPPT - 2000R -> battery. Murphy kicks in with no PV input route on the 2000R schematic. Other info is the 2000R controls a Xantrex Charger/Inverter.